Washington, Oct 20 (IANS): US President Donald Trump was closing in on his Democratic rival Joe Biden's lead in Pennsylvania, a key battleground state that could alter the results of a presidential election, a new poll has revealed.

According to the latest Reuters/Ipsos opinion poll released on Wednesday, Biden was in the lead with support from 49 per cent of registered voters, while Trump had the backing of 45 per cent, The Hill news agency reported.

In the October 5 Reuters/Ipsos opinion poll, Biden was backed by 50 per cent of the registered voters, while Trump support was unchanged at 45 per cent.

In mid-September, 49 per cent of Pennsylvania respondents backed Biden, while 46 per cent supported Trump.

In the 2016 presidential election, it was neck-and-neck between Trump and his then Democratic challenger Hillary Clinton.

The state swung in Trump's favour with 48.18 per cent of the votes, while Clinton garnered 47.46 per cent of the total ballots.

Recent polls of swing states have shown Biden ahead of or tying with the President.

Last week's Hill-Harris poll found the former Vice President with a 5 percentage point lead in Pennsylvania and tied with Trump in Florida.

His lead reached 11 percentage points in Michigan.